Baryon-to-photon ratio
= Baryon-to-photon ratio
{title2=$\eta$}
{wiki}
The baryon-to-photon ratio is the number density of baryons divided by the number density of photons. In the present universe it is of order $10^{-9}$.
= Baryon-to-photon ratio
{title2=$\eta$}
{wiki}
The baryon-to-photon ratio is the number density of baryons divided by the number density of photons. In the present universe it is of order $10^{-9}$.